Zeitschriftenartikel: „Swing bridges“

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Collazos-Arias, Felipe, und David García-Sánchez. „Adaptation And Resilience From A Maintenance Perspective For Swing Bridge. Lessons Learned In Recent Retrofitting Project Experiences“. IOP Conference Series: Materials Science and Engineering 1202, Nr. 1 (01.11.2021): 012027. http://dx.doi.org/10.1088/1757-899x/1202/1/012027.

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Abstract This paper collects all the existing swing bridges around the world to emphasize the high-level technology performed in the earliest 20th century and analyzes the recent experience in the rehabilitation and retrofitting of a singular swing steel bridge. The bridge over the Asón estuary at Treto, in the North of Spain, showed significant problems and the structural condition level was critical previously to its intervention in 2015. The rehabilitation project including the restoration of the structural and functional safety level of the structure was deled after material studies and tests were performed. The new updated of the structure from the old nineteenth centuries to the new standard codes was also performed. A part from the historical value of the bridges and the "green" and safe-security aspects, the intervention took into account all the social requirements of the population in the area who recovered the pride in this emblematic and centenarian infrastructure and it is, itself, a successful intervention from the resilient point of view.

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Griggs, Francis E. „American Swing Bridges 1797 to 1907“. Practice Periodical on Structural Design and Construction 16, Nr. 4 (November 2011): 170–85. http://dx.doi.org/10.1061/(asce)sc.1943-5576.0000072.

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HARITOS, NICHOLAS. „ASSESSING THE INFLUENCE OF MODIFICATIONS ON IN-SERVICE PERFORMANCE OF STRUCTURAL SYSTEMS USING VIBRATION MEASUREMENTS“. International Journal of Structural Stability and Dynamics 09, Nr. 04 (Dezember 2009): 729–44. http://dx.doi.org/10.1142/s0219455409003260.

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This paper outlines application of dynamic testing to three separate structures where evaluations of their in-service condition and performance were required. In two of these cases, both bridges, model updating procedures enabled identification of key structural properties for performing an integrity assessment. In the case of the first bridge, dynamic testing was able to demonstrate that the first attempt at introducing bandbeams to strengthen the bridge over its piers was virtually ineffective in stiffening the bridge. However, after these bandbeams were replaced, similar dynamic testing verified that the new work was now in fact so effective in stiffening this same bridge. Dynamic testing of the second bridge, a historical wrought iron swing bridge, was able to verify the integrity of the central pile group about which this bridge swings to allow riverboats to pass through. For the third case, involving a specialist laboratory floor system, a variety of excitation options were exercised to establish the acceptability of the floor to stringent criteria on vibration response levels.

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Ledsham, Gareth R., Lawrence Tall und Chris Armstrong. „Diglis swing bridges, UK – a case study of movable timber bridges“. Proceedings of the Institution of Civil Engineers - Bridge Engineering 164, Nr. 3 (September 2011): 167–81. http://dx.doi.org/10.1680/bren.2011.164.3.167.

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Liu, Tao, Jianfeng Fan und Ziqiang Peng. „Central Load-Bearing Control in the Construction Process of the Concrete Spherical Joint Nandu River Swing Bridge: A Case Study“. Buildings 12, Nr. 5 (20.04.2022): 511. http://dx.doi.org/10.3390/buildings12050511.

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The rotating mechanism is a significant procedure in swing bridges. In this paper, the Nandu River swing bridge is taken as an engineering case study to exhibit the critical technology of the monitoring process and the construction method of the swing bridge. The research focuses on the central load-bearing control system used to guarantee the security of the construction process. The mechanical problems during the construction process are discussed. Simultaneously, the cable tension and gravity center test are introduced. The non-Hertz contact theory is utilized to calculate the stress distribution of the spherical joint. Furthermore, the overturning moment is computed to monitor the stability of the rotating system based on the stress distribution calculation of the spherical joint. The monitoring process of central load-bearing control is entirely exhibited and discussed. Concurrently, the calculating result of the real-time overturning moment reflects the stability of the rotating construction process, and adjustments are made to ensure the safety of construction. The results show that, during the cable tension process, the middle position of the main arch exhibited 162.3 mm maximum vertical displacement. Meanwhile, the fraction moment was greatly larger than the unbalanced moment. Furthermore, the maximum overturning moment value was 2094.38 kN·m, which was smaller than the resistance of the overturning moment. The present research demonstrates that the non-Hertz contact theory fits the calculation of spherical joint stress distribution. Simultaneously, the middle position of the main arch should be monitored to control the vertical displacement at the cable tensioning stages. The gravity center test and stability control of the rotating construction are the key steps to reaching central load-bearing control.

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Abo-Elnor, Mootaz E. „Analysis of Different Bascule Bridge Architectures“. WSEAS TRANSACTIONS ON APPLIED AND THEORETICAL MECHANICS 17 (19.07.2022): 86–94. http://dx.doi.org/10.37394/232011.2022.17.12.

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Bascule bridges are widely used nowadays to overcome the obstruction of ships passage as crossing waterways and in some roadways to overcome transport vehicle height limitation. A Bascule bridge is a movable bridge with a counterweight that continuously balances a span, or "leaf", throughout its upward swing to provide clearance for boat or ship traffic. It may be single or double leafed. Balance Beam Bascule Bridge is one of the famous bascule bridge architecture in which bridge span counter balance weight is attached to a balance beam in the movable bridge operating mechanism. Although hydraulic cylinders is a particularly common solution to power majority of modern bascule bridges, it is very important to understand the kinematics and motion of the bridge leave for optimum operation of the bridge with prober counter balance selection. In this study a review of two operating hydraulic actuators arrangements; push arrangement and pull arrangement is carried out based on both design aspects and safety consideration. 3D model of the study mechanisms are constructed and a kinematics of bridge leaf (span) opening mechanisms are developed for early stage design configuration of bridge mechanism. kinematic analyses of bridge mechanism operation in both push and pull arrangements based on rigid body consideration is performed and Numerical analysis using finite element method is carried out in which stress distribution over tie rods is obtained. Some failure scenarios are introduced. Results show that tension forces acting on tie rods in pull arrangement is lower than that in push arrangement, work done by hydraulic cylinders (Actuators) in both arrangement is nearly identical and pull arrangement is much better than push arrangement from safety point of view.

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Kostianaia, Evgeniia A., und Andrey G. Kostianoy. „Railway Transport Adaptation Strategies to Climate Change at High Latitudes: A Review of Experience from Canada, Sweden and China“. Transport and Telecommunication Journal 24, Nr. 2 (01.04.2023): 180–94. http://dx.doi.org/10.2478/ttj-2023-0016.

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Abstract Impact of climate change on railway transport manifests in a variety of consequences, such as rail buckling, rail flooding, expansion of swing bridges, overheating of electrical equipment and its damage, bridge scour, failure of earthworks, ground settlement, pavement deterioration, damage to sea walls, coastal erosion of tracks and earthworks, and an increased number of railway accidents in general. Such impacts can cause considerable disruption of railway operations and lead to substantial financial expenses for repair of the railway infrastructure. Therefore, it is crucial to include adaptation strategies already in the design phase of the railway construction to ensure stability and integrity of the railway operations. This paper provides a literature review of adaptation considerations in Canada, China and Sweden and discusses climate change challenges that these countries face in their railway systems. In conclusion, the authors provide recommendations for adaptation approaches based on the reviewed international experience which can be useful for policymakers and managers of railway companies.

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Hu, Song, Ying Hua Ye, Sheng Gang Chen und Guan Zhong Song. „Experimental and Numerical Study of RC Thin-Walled Channel Beam under Torsion“. Applied Mechanics and Materials 405-408 (September 2013): 1196–99. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.1196.

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The reinforced concrete thin-walled channel beams are widely designed as bridges in urban railway and city roads. The swing force in the driving which cause constrained torsion becomes a safety factor. The torsion resistance of concrete members is not adequate to thin-walled channel beams, which is based on the theory of spatial truss with variable angle. An experiment was conducted to test the mechanical properties of the thin-walled channel beam under torsion. The mechanical properties of RC thin-walled channel beam under restrained torsion were also researched with Finite Element software, and were compared to the result of the experiment. The result of FE model agreed well with the experiment.

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Jontes, James D., und Ronald A. Milligan. „Brush Border Myosin–I Structure and ADP-dependent Conformational Changes Revealed by Cryoelectron Microscopy and Image Analysis“. Journal of Cell Biology 139, Nr. 3 (03.11.1997): 683–93. http://dx.doi.org/10.1083/jcb.139.3.683.

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Brush border myosin–I (BBM-I) is a single-headed myosin found in the microvilli of intestinal epithelial cells, where it forms lateral bridges connecting the core bundle of actin filaments to the plasma membrane. Extending previous observations (Jontes, J.D., E.M. Wilson-Kubalek, and R.A. Milligan. 1995. Nature [Lond.]. 378:751–753), we have used cryoelectron microscopy and helical image analysis to generate three-dimensional (3D) maps of actin filaments decorated with BBM-I in both the presence and absence of 1 mM MgADP. In the improved 3D maps, we are able to see the entire light chain–binding domain, containing density for all three calmodulin light chains. This has enabled us to model a high resolution structure of BBM-I using the crystal structures of the chicken skeletal muscle myosin catalytic domain and essential light chain. Thus, we are able to directly measure the full magnitude of the ADP-dependent tail swing. The ∼31° swing corresponds to ∼63 Å at the end of the rigid light chain–binding domain. Comparison of the behavior of BBM-I with skeletal and smooth muscle subfragments-1 suggests that there are substantial differences in the structure and energetics of the biochemical transitions in the actomyosin ATPase cycle.

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Huang, Can, Yongwei Wang, Shuyuan Xu, Wenchi Shou, Chengming Peng und Danfeng Lv. „Vision-Based Methods for Relative Sag Measurement of Suspension Bridge Cables“. Buildings 12, Nr. 5 (17.05.2022): 667. http://dx.doi.org/10.3390/buildings12050667.

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Main cables, comprising a number of wire strands, constitute a vital element in long-span suspension bridges. The determination of their alignment during construction is of great importance, and relative sag is commonly measured for the efficient sag adjustment of general strands. The conventional approach uses the caterpillar method, which is inconvenient, difficult-to-implement, and potentially dangerous. In order to realize the high-precision measurement of cable alignment in a strong wind environment, a vision-based method for relative sag measurement of the general cable strands is proposed in this paper. In the proposed measurement system, images of pre-installed optical targets are collected and analyzed to realize the remote, automatic, and real-time measurement of the relative sag. The influences of wind-induced cable shaking and camera shaking on the accuracy of the height difference measurement are also theoretically analyzed. The results show that cable strand torsion and camera roll have a great impact on the measurement accuracy, while the impacts of the cable strand swing and vibration, camera swing and vibration, and camera pitch and yaw are insignificant. The vision-based measurement system tested in the field experiment also shows a measurement error within 3 mm, which meets the requirements for cable adjustment construction. At the same time, the vision-based measurement method proposed and validated in this paper can improve the measurement accuracy and efficiency of strand alignment in a strong wind environment. Potential risks involved in the manual measurement, e.g., working at heights and in strong wind environments, can be eliminated, facilitating the automation of the cable erection process.

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Castillo, Bryan, Johannio Marulanda und Peter Thomson. „Experimental Evaluation of Pedestrian-Induced Multiaxial Gait Loads on Footbridges: Effects of the Structure-to-Human Interaction by Lateral Vibrating Platforms“. Sensors 24, Nr. 8 (14.04.2024): 2517. http://dx.doi.org/10.3390/s24082517.

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The introduction of resistant and lightweight materials in the construction industry has led to civil structures being vulnerable to excessive vibrations, particularly in footbridges exposed to human-induced gait loads. This interaction, known as Human–Structure Interaction (HSI), involves a complex interplay between structural vibrations and gait loads. Despite extensive research on HSI, the simultaneous effects of lateral structural vibrations with fundamental frequencies close to human gait frequency (around 1.0 Hz) and wide amplitudes (over 30.0 mm) remain inadequately understood, posing a contemporary structural challenge highlighted by incidents in iconic bridges like the Millennium Bridge in London, Solferino Bridge in Paris, and Premier Bridge in Cali, Colombia. This paper focuses on the experimental exploration of Structure-to-Human Interaction (S2HI) effects using the Human–Structure Interaction Multi-Axial Test Framework (HSI-MTF). The framework enables the simultaneous measurement of vertical and lateral loads induced by human gait on surfaces with diverse frequency ranges and wide-amplitude lateral harmonic motions. The study involved seven test subjects, evaluating gait loads on rigid and harmonic lateral surfaces with displacements ranging from 5.0 to 50.0 mm and frequency content from 0.70 to 1.30 Hz. A low-cost vision-based motion capture system with smartphones analyzed the support (Tsu) and swing (Tsw) periods of human gait. Results indicated substantial differences in Tsu and Tsw on lateral harmonic protocols, reaching up to 96.53% and 58.15%, respectively, compared to rigid surfaces. Normalized lateral loads (LL) relative to the subject’s weight (W0) exhibited a linear growth proportional to lateral excitation frequency, with increased proportionality constants linked to higher vibration amplitudes. Linear regressions yielded an average R2 of 0.815. Regarding normalized vertical load (LV) with respect to W0, a consistent behavior was observed for amplitudes up to 30.0 mm, beyond which a linear increase, directly proportional to frequency, resulted in a 28.3% increment compared to rigid surfaces. Correlation analyses using Pearson linear coefficients determined relationships between structural surface vibration and pedestrian lateral motion, providing valuable insights into Structure-to-Human Interaction dynamics.

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Rembold, C. M. „Relaxation, [Ca2+]i, and the latch-bridge hypothesis in swine arterial smooth muscle“. American Journal of Physiology-Cell Physiology 261, Nr. 1 (01.07.1991): C41—C50. http://dx.doi.org/10.1152/ajpcell.1991.261.1.c41.

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During vascular smooth muscle relaxation, myosin light-chain phosphorylation values decrease to resting values more rapidly than do stress values. Because phosphorylation is proportionally low, the latch-bridge hypothesis predicts that stress during relaxation should be predominantly carried by latch bridges. I evaluated the mechanical properties of latch bridges by changing tissue length and measuring myoplasmic Ca2+ concentration ([Ca2+]) with aequorin during relaxation of swine carotid medial tissues. Stress production was predicted with the latch-bridge model of Hai and Murphy, in which the measured aequorin [Ca2+] signal is the only determinant of stress. The aequorin-based latch-bridge model predicted relaxation induced by removal of the histamine stimulation. However, when tissues were relaxed by removal of extracellular Ca2+ or Ca(2+)-channel blockers in the continued presence of histamine, the aequorin-based model modestly underestimated the resulting relaxation. This underestimation was most likely caused by a small increase in the [Ca2+] sensitivity of phosphorylation since a model with an altered [Ca2+] sensitivity of phosphorylation more accurately predicted the resulting relaxation. The time course of relaxation in swine carotid artery was not substantially altered when the tissue was either briefly stretched or shortened and then returned to the original length. Because stretch should detach cross bridges, I modified the aequorin-based latch-bridge model to account for stretch-induced cross-bridge detachment. Because [Ca2+] values were slightly above resting values both before and after the stretch, the model predicted that phosphorylated cross bridges could reattach, be dephosphorylated, and form new latch bridges. The model predicted relaxation except during the first few seconds after stretch. These results suggest that latch-bridge reattachment is not necessary to explain the majority of the response to stretch during relaxation. The rate-limiting step for relaxation appears to be removal of [Ca2+] and not latch-bridge detachment.

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Qian, Xiaolan, Wenchen Han und Junzhong Yang. „From the DeGroot Model to the DeGroot-Non-Consensus Model: The Jump States and the Frozen Fragment States“. Mathematics 12, Nr. 2 (10.01.2024): 228. http://dx.doi.org/10.3390/math12020228.

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Non-consensus phenomena are widely observed in human society, but more attention is paid to consensus phenomena. One famous consensus model is the DeGroot model, and there are a series of outstanding works derived from it. By introducing the cognition bias, resulting in over-confidence and under-confidence in the DeGroot model, we propose a non-consensus model, namely the DeGroot-Non-Consensus model. It bridges consensus phenomena and non-consensus phenomena. While different in meaning, the new opinion model can reproduce the DeGroot model’s behaviors and supply a series of interesting non-consensus states. We find frozen fragment states for the over-confident population and time-dependent states for strong interaction strength. In frozen fragment states, the population is polarized into opinion clusters formed by extremists. In time-dependent states, agents jump between two opinions that only differ in the sign, which provides a possible explanation for the swing in opinions in elections and the fluctuations in open questions in the absence of external information. All of these states are summarized in the phase diagrams of the self-confidence and the interaction strength plane. Moreover, the transition scenarios along different parameter paths are studied. Meanwhile, the influence of the nodes’ degree is illustrated in the phase diagrams and the relationship is given. The finite size effect is found in the not quite over-confident population. An interesting phenomenon for small population sizes is that neutral populations with large opinion variance are robust to the fluctuations induced by a finite population size.

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Di Blasi, P., D. Van Riper, R. Kaiser, C. M. Rembold und R. A. Murphy. „Steady-state dependence of stress on cross-bridge phosphorylation in the swine carotid media“. American Journal of Physiology-Cell Physiology 262, Nr. 6 (01.06.1992): C1388—C1391. http://dx.doi.org/10.1152/ajpcell.1992.262.6.c1388.

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Tonic contractions of the swine carotid media are typically characterized by initial transients in myoplasmic [Ca2+] and cross-bridge phosphorylation followed by force maintenance with reduced intracellular [Ca2+] and cross-bridge phosphorylation (“latch”). The presence of effective mechanisms in the carotid media to limit steady-state myoplasmic [Ca2+] and cross-bridge phosphorylation to modest increases over resting values has limited experimental attempts to determine the dependence of active stress (force/tissue cross-sectional area) on cross-bridge phosphorylation. In this study, we employed stimulation protocols that combined effective contractile agonists with inhibitors of Ca2+ extrusion or sequestration to achieve high steady-state levels of cross-bridge phosphorylation (up to 60%). Increases in cross-bridge phosphorylation from 30 to 60% were not associated with significant increases in stress in agreement with the predictions of Hai and Murphy [Am. J. Physiol. 254 (Cell Physiol. 23): C99-C106, 1988] four-state cross-bridge model for the carotid media. Thus cross-bridge phosphorylation may suffice to determine force generation in vascular smooth muscle if both phosphorylated and dephosphorylated attached cross bridges (or latch bridges) contribute to active stress.

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Patil, Rahul, Yash Nimbalkar, Satyajeet Chavan und Abhijeet Mahajan. „Golf Swing Analysis using Computer Vision“. International Journal for Research in Applied Science and Engineering Technology 11, Nr. 5 (31.05.2023): 3700–3704. http://dx.doi.org/10.22214/ijraset.2023.52514.

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Abstract: Sports play a significant role in providing entertainment and recreational activities. As technology has advanced, video games featuring various sports and games have been developed using computer vision. In the game of golf, the golf swing is a crucial element that involves the entire body when players strike the ball. Having the correct posture is essential for a strong swing. However, beginners often struggle with identifying the keyframes they should focus on and which areas of their body they need to improve due to uneven timing and lack of expertise. To bridge this gap, this research proposes a neural network-based system for analyzing golf swings. The system utilizes monocular swing footage to offer an autonomous method for estimating the golfer's movement. Since amateur players often lack supervision during self-practice, this method can be particularly useful. The research also includes the design of an architecture that combines parts detection and parts association using image processing. By temporally aligning the swing videos, the system can estimate the golfer's pose, which can be further utilized for analysis.

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Chung, Su-Wan, Sung-Sam Hong und Byung-Kon Kim. „Performance Comparison of Deep Learning Models for Damage Identification of Aging Bridges“. Applied Sciences 13, Nr. 24 (12.12.2023): 13204. http://dx.doi.org/10.3390/app132413204.

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Currently, damage in aging bridges is assessed visually, leading to significant personnel, time, and cost expenditures. Moreover, the results depend on the subjective judgment of the inspector. Machine-learning-based approaches, such as deep learning, can solve these problems. In particular, instance-segmentation models have been used to identify different types of bridge damage. However, the value of deep-learning-based damage identification may be reduced by insufficient training data, class imbalance, and model-reliability issues. To overcome these limitations, this study utilized photographic data from real bridge-management systems for the inspection and assessment of bridges as the training dataset. Six types of damage were considered. Moreover, the performances of three representative deep learning models—Mask R-CNN, BlendMask, and SWIN—were compared in terms of loss–function values. SWIN showed the best performance, achieving a loss value of 0.000005 after 269,939 training iterations. This shows that bridge-damage-identification performance can be maximized by setting an appropriate learning rate and using a deep learning model with a minimal loss value.

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Yu, Zhan Dong, Jiang Tao Xu und Xian Feng Wang. „Position and Anti-Swing Control Based on BVP Arithmetic for Bridge Cranes“. Advanced Materials Research 287-290 (Juli 2011): 3102–5. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.3102.

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The anti-swing problem of the bridge cranes is discussed. The position and anti-swing control strategy based on BVP arithmetic is presented. The position and anti-swing control programming of bridge cranes can be transformed into the two-point boundary value problem (BVP) of nonlinear systems. According to the boundary conditions, the tractive force function of Fourier series form with free parameters is constructed. The BVP is solved with the bvp4c function in Matlab toolbox, and the tractive force sequence is obtained. The presented position and anti-swing control strategy for bridge cranes belongs to open-loop feedforward control essentially. The simulation of anti-swing and position control process illustrates the effectivity of the control strategy.

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Yu, Zhen, Hao-Ming Dong und Chang-Ming Liu. „Research on Swing Model and Fuzzy Anti Swing Control Technology of Bridge Crane“. Machines 11, Nr. 6 (23.05.2023): 579. http://dx.doi.org/10.3390/machines11060579.

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A bridge crane is often used in a complex environment and is often subject to the interference of all loads. Some uncertain factors often have an inevitable impact on its swing. So the force situation of the bridge crane during a working cycle is analyzed, and a three-dimensional dynamic mathematical model of the bridge crane is built. Through the simulation analysis of the model under the action of a driving force and wind load, the change law of the swing angle of the bridge crane is studied. Then, the fuzzy control theory is used to determine the control parameter in the anti-sway control process. The position, swing angle deviation, and deviation rate of the bridge crane are taken as the input, and the parameter correction is obtained after the fuzzification by using the center of gravity method. The anti-sway fuzzy control system of the bridge crane is designed and simulated. The research results show that the swing model of the crane is reasonable and the fuzzy PID anti-sway controller can not only improve the adaptability of the control system, but also overcome the large overshoot, quickly restrain the swing, and effectively realize the anti-sway function of the bridge crane.

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Feng, Yin’an, Hao Zhang und Chan Gu. „The Prescribed-Time Sliding Mode Control for Underactuated Bridge Crane“. Electronics 13, Nr. 1 (03.01.2024): 219. http://dx.doi.org/10.3390/electronics13010219.

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In this article, a prescribed-time sliding mode controller is proposed for the design of the positioning and anti-swing time of the underactuated bridge crane under different initial conditions. Compared with the existing crane positioning and anti-swing controller, the controller can directly specify the positioning and anti-swing time of the bridge crane system through the controller parameters. Firstly, in order to solve the underdrive problem of the bridge crane system, the crane system model is transformed by constructing composite variables; secondly, a new prescribed-time convergence rate and a new prescribed-time sliding mode surface are designed to ensure that the state of the bridge crane system can converge within the prescribed time; finally, the Lyapunov stability analysis and simulation results show that the designed controller can enable the crane to position and anti-swing within the prescribed time.

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Hidayat, Nailul, Yufrizal A, Hendri Nurdin, Farid Kassimov und Elnar Kenzhaliyev. „Installation of gussets to reduce stress on the junction between the arm and bridge on the swing arm“. Journal of Engineering Researcher and Lecturer 2, Nr. 2 (28.07.2023): 14–20. http://dx.doi.org/10.58712/jerel.v2i2.75.

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The swing arm is one of the main components of a motorcycle that functions as a connection between the rear wheel and the frame. Under loading conditions, the joint area between the arm and the bridge experiences significant stress, leading to fractures in that region. This study aims to investigate the effectiveness of installing gussets to reduce the stress that occurs at the joint area between the arm and the bridge in the swing arm of ELGO electric motorcycles. The research was conducted using the static analysis simulation method with Solidworks 2021-2022 Research License software. The loading conditions were simulated based on the actual usage of the electric motorcycle. The simulation results revealed that without the installation of gussets, the joint area between the arm and the bridge in the swing arm experienced stress exceeding the yield strength of the material. This would inevitably lead to the breakage of the swing arm and potentially cause accidents for motorcycle riders. However, after the gussets were installed, the stress at the joint area between the arm and the bridge remained below the yield strength of the material. Based on these findings, it can be concluded that the installation of gussets successfully reduced the stress at the joint area between the arm and the bridge in the swing arm. This research outcome can serve as a reference for the design of swing arms for electric motorcycles.

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Thomsen, Kjeld. „Odin’s Bridge—Europe’s Longest Twin Swing Bridge, Denmark“. Structural Engineering International 25, Nr. 2 (Mai 2015): 208–12. http://dx.doi.org/10.2749/101686615x14210663188457.

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Ratz, P. H., C. M. Hai und R. A. Murphy. „Dependence of stress on cross-bridge phosphorylation in vascular smooth muscle“. American Journal of Physiology-Cell Physiology 256, Nr. 1 (01.01.1989): C96—C100. http://dx.doi.org/10.1152/ajpcell.1989.256.1.c96.

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Cross-bridge phosphorylation associated with agonist-stimulated contraction of vascular smooth muscle is often transiently elevated. Such observations led to the concept that phosphorylation of the 20-kDa myosin regulatory light chain (Mp) was required for initial activation and cross-bridge cycling but might not be necessary for steady-state maintenance of stress in the latch state. The possibility that stress maintenance is not regulated by phosphorylation has received some experimental support in contractions induced by phorbol esters and the calcium channel activator BAY K 8644 in which significant increases in Mp were not detected. Our aim was to test the hypothesis that phosphorylation is both necessary and sufficient for activation and for maintenance of steady-state stress. Activation of swine carotid media using agents that bypass receptor activation and elevate Ca2+ influx without mobilizing intracellular Ca2+ stores (BAY K 8644 and ionomycin) produced monotonic increases in both stress and Mp. Transient initial peaks in Mp were absent. Steady-state stress induced by both receptor- and nonreceptor-mediated activation was dependent on small increases in Mp. Increases in Mp greater than 0.3 mol Pi/mol myosin light chain had small effects on stress but produced large increases in the maximum rate of cross-bridge cycling at zero load (Vo). The experimentally determined dependence of stress on Mp was quantitatively predicted by our working hypothesis. This model proposes that Ca2+-stimulated cross-bridge phosphorylation is obligatory for cross-bridge attachment. However, dephosphorylation of attached cross bridges to form noncycling "latch bridges" allows stress maintenance with reduced Mp and cycling.

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Rembold, Christopher M., Robert L. Wardle, Christopher J. Wingard, Timothy W. Batts, Elaine F. Etter und Richard A. Murphy. „Cooperative attachment of cross bridges predicts regulation of smooth muscle force by myosin phosphorylation“. American Journal of Physiology-Cell Physiology 287, Nr. 3 (September 2004): C594—C602. http://dx.doi.org/10.1152/ajpcell.00082.2004.

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Serine 19 phosphorylation of the myosin regulatory light chain (MRLC) appears to be the primary determinant of smooth muscle force development. The relationship between MRLC phosphorylation and force is nonlinear, showing that phosphorylation is not a simple switch regulating the number of cycling cross bridges. We reexamined the MRLC phosphorylation-force relationship in slow, tonic swine carotid media; fast, phasic rabbit urinary bladder detrusor; and very fast, tonic rat anococcygeus. We found a sigmoidal dependence of force on MRLC phosphorylation in all three tissues with a threshold for force development of ∼0.15 mol Pi/mol MRLC. This behavior suggests that force is regulated in a highly cooperative manner. We then determined whether a model that employs both the latch-bridge hypothesis and cooperative activation could reproduce the relationship between Ser19-MRLC phosphorylation and force without the need for a second regulatory system. We based this model on skeletal muscle in which attached cross bridges cooperatively activate thin filaments to facilitate cross-bridge attachment. We found that such a model describes both the steady-state and time-course relationship between Ser19-MRLC phosphorylation and force. The model required both cooperative activation and latch-bridge formation to predict force. The best fit of the model occurred when binding of a cross bridge cooperatively activated seven myosin binding sites on the thin filament. This result suggests cooperative mechanisms analogous to skeletal muscle that will require testing.

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Eisenberg, Y. „PIER PROTECTION SYSTEM FOR THE DUWAMISH SHIP CHANNEL IN SEATTLE“. Coastal Engineering Proceedings 1, Nr. 20 (29.01.1986): 137. http://dx.doi.org/10.9753/icce.v20.137.

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In 1978 an out-of-control ship hit and severely damaged a bascule bridge across the Duwamish West Waterway in Seattle seriously affecting both ship and highway traffic. The high level West Seattle Bridge was subsequently constructed to handle all through-highway traffic. A swing bridge was also designed to handle local traffic over the ship channel. The function of the pier protection system described in this paper is to protect the pivot piers and swing spans of this new bridge from damage by absorbing the part of the tranverse energy component imparted by a colliding ship, which is not absorbed by deformation of the ship's hull.

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Fuchs, N., K. Tomlinson und R. Buckby. „El Ferdan Bridge, Egypt: the world's longest swing bridge“. Proceedings of the Institution of Civil Engineers - Bridge Engineering 156, Nr. 1 (März 2003): 21–30. http://dx.doi.org/10.1680/bren.2003.156.1.21.

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Lin, Haojie, und Xuyang Lou. „Data-Driven Active Learning Control for Bridge Cranes“. Mathematical and Computational Applications 28, Nr. 5 (09.10.2023): 101. http://dx.doi.org/10.3390/mca28050101.

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For positioning and anti-swing control of bridge cranes, the active learning control method can reduce the dependence of controller design on the model and the influence of unmodeled dynamics on the controller’s performance. By only using the real-time online input and output data of the bridge crane system, the active learning control method consists of the finite-dimensional approximation of the Koopman operator and the design of an active learning controller based on the linear quadratic optimal tracking control. The effectiveness of the control strategy for positioning and anti-swing of bridge cranes is verified through numerical simulations.

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Taylor, A., C. Plant und J. Dickerson. „Wellington Street Swing Bridge, Hull, UK“. Proceedings of the Institution of Civil Engineers - Engineering History and Heritage 162, Nr. 2 (Mai 2009): 67–79. http://dx.doi.org/10.1680/ehh.2009.162.2.67.

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Clark, John H. „West Seattle Swing Bridge, Seattle, Washington“. Structural Engineering International 5, Nr. 1 (Februar 1995): 23–25. http://dx.doi.org/10.2749/101686695780601475.

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Zhong, Guo Wen, und Hua Cao. „Electromagnetic Motion Device Based on LPC2131 of PID Control“. Advanced Materials Research 898 (Februar 2014): 919–23. http://dx.doi.org/10.4028/www.scientific.net/amr.898.919.

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Design of a ARM7 LPC2131 as the control core, through the H bridge chip LN298 driver power through the coil produces a changing magnetic field, the magnetic deflection force start swinging of the swing rod, the angle sensor (model MPU6050) feedback magnet swing angle signal, control coil magnetic field by using PID technology, so as to the electromagnetic force to precisely control the pendulum swing angle of the objective, by the TFT liquid crystal display pendulum swing angle, cycle, response time, stop time.

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Moreland, R. S., und S. Moreland. „Characterization of magnesium-induced contractions in detergent-skinned swine carotid media“. American Journal of Physiology-Cell Physiology 260, Nr. 6 (01.06.1991): C1224—C1232. http://dx.doi.org/10.1152/ajpcell.1991.260.6.c1224.

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Ca(2+)-calmodulin-dependent phosphorylation of the 20-kDa smooth muscle myosin light chain (MLC) results in high shortening velocities and rapid stress development. The stress maintained after a reduction in Ca2+ is associated with a decrease in MLC phosphorylation and velocity of shortening. This Ca(2+)-dependent stress without proportional MLC phosphorylation has been termed “latch” and has been postulated to reflect a population of dephosphorylated noncycling cross bridges or “latch bridges.” Mg2+ is necessary for contraction of smooth muscle, and in high concentrations, Mg2+ elicits contractions that are MLC phosphorylation independent. The purpose of this study was to test the hypothesis that high concentrations of Mg2+ directly induce latch-bridge formation. This was accomplished by comparing the characteristics of Mg(2+)-induced contractions of Triton X-100-skinned swine carotid media with the known characteristics of the Ca(2+)-dependent latch state. In the absence of Ca2+, free Mg2+ (3-20 mM) caused an increase in the velocity of shortening and a concentration-dependent increase in stress, with no detectable increase in MLC phosphorylation. Mg(2+)-induced contractions could be supported by CTP, which is a substrate for the actin-activated myosin adenosinetriphosphatase but not the MLC kinase. Stress development in response to Mg2+ was abolished at long tissue lengths, which also inhibit the expression of latch bridges. The calmodulin antagonist, trifluoperazine (TFP), inhibited the MLC phosphorylation-independent contractions elicited by Mg2+. TFP also inhibited the latch state. The results of this study support the existence of a regulatory system in vascular smooth muscle that is independent of the MLC phosphorylation system and can be directly activated by pharmacological levels of Mg2+.

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Li, Hui, Yanbo Hui, Jun Ma, Qiao Wang, Ying Zhou und Hongxiao Wang. „Research on Variable Universe Fuzzy Multi-Parameter Self-Tuning PID Control of Bridge Crane“. Applied Sciences 13, Nr. 8 (12.04.2023): 4830. http://dx.doi.org/10.3390/app13084830.

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The bridge-type bridge crane is a common lifting equipment used in modern factories and workshops. During the crane’s operation, the positioning of the trolley and the swing of the load can significantly impact the bridge crane’s safety and reliability. In this paper, we propose a variable universe fuzzy multi-parameter self-tuning PID (VUFMS-PID) control strategy for controlling the trolley’s movement. Our control strategy uses scaling factor variation to dynamically adjust the number of fuzzy control rules based on the system error and error rate of change. This approach improves control accuracy and enhances the crane’s stability and safety. Simulation results demonstrate that our proposed control strategy outperforms both the fuzzy PID and traditional PID control strategies. Specifically, it reduces the crane trolley’s positioning time and the maximum swing angle of the load. Our control strategy exhibits good adaptive ability and robustness, which further improves the stability and safety of the bridge-type bridge crane operation.

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Moreland, S., und R. S. Moreland. „Effects of dihydropyridines on stress, myosin phosphorylation, and V0 in smooth muscle“. American Journal of Physiology-Heart and Circulatory Physiology 252, Nr. 6 (01.06.1987): H1049—H1058. http://dx.doi.org/10.1152/ajpheart.1987.252.6.h1049.

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Contraction of swine carotid medial fibers with KCl results in stress development associated with high levels of myosin light chain (MLC) phosphorylation and maximum shortening velocity (V0) indicative of rapidly cycling phosphorylated cross bridges. The period of stress maintenance is characterized by low levels of MLC phosphorylation and V0; the maintained stress is postulated to be supported by dephosphorylated, slowly cycling cross bridges (latch bridges). This study was designed to examine the roles of calcium in both stress development and stress maintenance. Medial strips were contracted with 110 mM KCl in the presence of varying concentrations of the calcium channel blocker nifedipine (1-100 nM) or were contracted with varying concentrations of the calcium channel activator BAY-K 8644 (0.3-3 microM). Nifedipine significantly depressed stress maintenance and V0, but had little effect on either stress development or MLC phosphorylation. Conversely, BAY-K 8644 produced contractions that were equal to those elicited with 110 mM KCl but that were characterized by low levels of V0 and basal or low levels of MLC phosphorylation. These data suggest that the mechanisms by which the cellular calcium concentration increases and the limitations on this increase may impact differently on different regulatory processes of contraction and, thereby, on cross bridge behavior.

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Chen, Zhi-mei, Wen-jun Meng und Jing-gang Zhang. „Intelligent anti-swing control for bridge crane“. Journal of Central South University 19, Nr. 10 (Oktober 2012): 2774–81. http://dx.doi.org/10.1007/s11771-012-1341-6.

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Thomsen, Kjeld, und Knud Erik Pedersen. „Swing Bridge across a Navigation Channel, Denmark“. Structural Engineering International 8, Nr. 3 (August 1998): 201–4. http://dx.doi.org/10.2749/101686698780489225.

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Crotti, Stefania, Nicola Bottino, Giulia Maria Ruggeri, Elena Spinelli, Daniela Tubiolo, Alfredo Lissoni, Alessandro Protti und Luciano Gattinoni. „Spontaneous Breathing during Extracorporeal Membrane Oxygenation in Acute Respiratory Failure“. Anesthesiology 126, Nr. 4 (01.04.2017): 678–87. http://dx.doi.org/10.1097/aln.0000000000001546.

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Abstract Background We evaluate the clinical feasibility of spontaneous breathing on extracorporeal membrane oxygenation and the interactions between artificial and native lungs in patients bridged to lung transplant or with acute exacerbation of chronic obstructive pulmonary disease (COPD) or acute respiratory distress syndrome. Methods The clinical course of a total of 48 patients was analyzed. Twenty-three of 48 patients were enrolled in the prospective study (nine bridged to lung transplant, six COPD, and eight acute respiratory distress syndrome). The response to the carbon dioxide removal was evaluated in terms of respiratory rate and esophageal pressure swings by increasing (“relief” threshold) and decreasing (“distress” threshold) the extracorporeal membrane oxygenation gas flow, starting from baseline condition. Results Considering all 48 patients, spontaneous breathing extracorporeal membrane oxygenation was performed in 100% bridge to lung transplant (9 of 9 extubated), 86% COPD (5 of 6 extubated), but 27% acute respiratory distress syndrome patients (6 of 8 extubated; P < 0.001) and was maintained for 92, 69, and 38% of the extracorporeal membrane oxygenation days (P = 0.021), respectively. In all the 23 patients enrolled in the study, gas flow increase (from 2.3 ± 2.2 to 9.2 ± 3.2 l/min) determined a decrease of both respiratory rate (from 29 ± 6 to 8 ± 9 breaths/min) and esophageal pressure swings (from 20 ± 9 to 4 ± 4 cm H2O; P < 0.001 for all). All COPD and bridge to lung transplant patients were responders (reached the relief threshold), while 50% of acute respiratory distress syndrome patients were nonresponders. Conclusions Carbon dioxide removal through extracorporeal membrane oxygenation relieves work of breathing and permits extubation in many patients, mainly bridge to lung transplant and COPD. Only few patients with acute respiratory distress syndrome were able to perform the spontaneous breathing trial, and in about 50% of these, removal of large amount of patient’s carbon dioxide production was not sufficient to prevent potentially harmful spontaneous respiratory effort.

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Song, Xueping, Zhuoxuan Li, Jiankang Huang, Ding Fan und Shurong Yu. „Analysis of Droplet Transfer and Arc Swing in “TIG + AC” Twin-Wire Cross Arc Additive Manufacturing“. Metals 13, Nr. 1 (26.12.2022): 63. http://dx.doi.org/10.3390/met13010063.

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Twin-wire and arc additive manufacturing (T-WAAM) has potential advantages in improving deposition efficiency and manufacturing functionally graded materials (FGMs), thus attracting much attention. However, there are few studies on the droplet transfer mode of T-WAAM. This paper analyzes the droplet transfer mode and arc swing in the “TIG + AC” twin-wire cross-arc additive manufacturing by in-situ observation with high-speed photography, revealing what factors influence the T-WAAM on deposition shaping the quality and what are the key mechanisms for process stability. Experiments show that with the main arc current provided by TIG 100 A and the twin-wire AC arc current 10 A, three different droplet transfer modes, namely the “free transfer + free transfer, bridge transfer + free transfer, bridge transfer + bridge transfer,” can be observed with the twin wires under different feeding speeds. The corresponding deposition and arc swing are quite different in quality. Through comparative analysis, it is found that the frequent extinguishment and ignition of the arc between electrode wires is the main factor for the instability in the additive manufacturing process. The “bridge transfer + free transfer” mode can obtain a large arc swing angle and a stable deposition, in which the cross arc has a significant stirring effect on the molten pool, and the deposition shape is well-made.

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Zhou, Yong, Xinyuan Zhang, Zhenzhen Yu, Dingena Schott und Gabriel Lodewijks. „An improved zero vibration method and parameter sensitivity analysis for the swing control of bridge-type grab ship unloader“. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 230, Nr. 14 (30.07.2015): 2463–72. http://dx.doi.org/10.1177/0954406215597957.

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This paper presents an improved zero vibration method for the swing control of bridge-type grab ship unloader. With the method, the concepts of equivalent frequency and the equivalent damping ratio are proposed to cope with the changeable length of rope, and the optimal path planning is considered to avoid collision and improve efficiency. Numerical simulation results of a case study indicate that the maximum residual swing angle of the grab can be limited to a small range to ensure safety using the improved zero vibration method, whereas the traditional zero vibration method with average frequency and zero damping ratio gets poor results of swing control. After that, the sensitivities of the max residual swing angle to the changes of some main design parameters (damping coefficient, deviation of the center of gravity of the grab in rope direction, and time delay of the system) and operating parameters (position deviation of the trolley, initial length deviation of the rope, and initial swing angle) are analyzed. The results obtained display that the residual swing angle is sensitive to the deviation of grab’s center of gravity, the deviation of trolley’s position, and the initial swing angle under the same control parameters, but insensitive to the damping coefficient, the time delay of the system, and the initial length deviation of the rope. This can help to select the appropriate parameter values or adaptive range in an actual unloader.

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Zeng, Zhi Hui, und Liang Li. „Research on Anti-Swing Control of Bridge Crane Based on Fuzzy Control“. Applied Mechanics and Materials 143-144 (Dezember 2011): 293–96. http://dx.doi.org/10.4028/www.scientific.net/amm.143-144.293.

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In recent years, with the development of intelligent control theory, fuzzy control theory has been applied to automatic control of the crane. This paper designs fuzzy anti-swing controller based on the nonlinear mathematical model of bridge crane, and MATLAB/Simulink simulation was carried out. The Simulink experiment proves that location fuzzy controller and angle fuzzy controller show the good anti-swing effect compared with conventional PID controller. The two controllers not only improve response speed times but also improve control accuracy.

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Marques da Silva, Fernando. „Aerodynamic Characterization of the 516 Arouca Pedestrian Suspension Bridge over the Paiva River“. Wind 3, Nr. 1 (14.02.2023): 79–96. http://dx.doi.org/10.3390/wind3010006.

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Given the 516 Arouca pedestrian suspension bridge’s design and characteristics, the owner, a municipality, required a set of tests in order to evaluate its aerodynamic characteristics and dynamic response, aiming at both structural safety and user comfort. Wind tunnel tests were performed over a sectional scaled model to obtain the static aerodynamic coefficients and dynamic response. The tests were carried out on different bridge configurations—a deck with people and a deck with an arch for secondary cables (connecting each suspension point to the catenary on the opposite side of the deck)—for the static coefficients. For the dynamic response, only the deck alone was tested. A major challenge had to be overcome, as the main displacement mode belonged to a swing movement, to assemble a wind tunnel setting, requiring a suspension system allowing wind displacements. A persistent trend of small amplitude displacements was identified, influencing user comfort and contributing to the installation of the secondary cables, but no aerodynamic instabilities were identified.

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Wu, Qingxiang, Ning Sun und Xiaokai Wang. „Equivalent Rope Length-Based Trajectory Planning for Double Pendulum Bridge Cranes with Distributed Mass Payloads“. Actuators 11, Nr. 1 (17.01.2022): 25. http://dx.doi.org/10.3390/act11010025.

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The hoisting form in which the payload is hung on the hook by two rigging ropes is widely used in the industry, but it also results in the complex double pendulum dynamic of the bridge crane, making the anti-swing trajectory planning full of challenges. In this paper, based on the concept of the equivalent rope length, an equivalent single pendulum model of the double pendulum bridge crane with the distributed mass payload is established. On this basis, the particle swarm optimization algorithm is adopted to solve the equivalent rope length and calculate the parameters of the anti-swing velocity trajectory based on the phase plane method. To evaluate the effectiveness of the proposed method, experiments with a laboratory double pendulum bridge crane are conducted. Experimental results demonstrate that the residual oscillation angle of the payload of the proposed method is smaller than those of the existing methods, such as the trajectory planning without the equivalent rope length, input shaping and command smoothing.

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Li, Hui, Yan-Bo Hui, Qiao Wang, Hong-Xiao Wang und Lin-Jun Wang. „Design of Anti-Swing PID Controller for Bridge Crane Based on PSO and SA Algorithm“. Electronics 11, Nr. 19 (30.09.2022): 3143. http://dx.doi.org/10.3390/electronics11193143.

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Since the swing of the lifting load and the positioning of the trolley during the operation of a bridge crane seriously affect the safety and reliability of its work, we have not only designed Proportional Integral Derivative (PID) controllers for the anti-swing and positioning control but also proposed a hybrid Particle Swarm Optimization (PSO) and Simulated Annealing (SA) algorithm to optimize the gains of the controllers. In updating the PSO algorithm, a nonlinear adaptive method is utilized to update the inertia weight and learning coefficients, and the SA algorithm is also integrated when the PSO algorithm is searching for a global optimal solution, to reduce the probability of falling into the local optimal solution. The simulation results demonstrate that the PSO–SA algorithm proposed in this paper is prone to be a more effective method in searching for the optimal parameters for the controllers, compared with three other algorithms. As shown by the experimental results, the swing angle stabilization time of the novel algorithm is 6.9 s, while the values of the other algorithms range from 10.3 to 13.1 s under a common working condition. Simultaneously, the maximum swing angle of the novel algorithm is 7.8°, which is also better than the other algorithms.

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Liang, Han, Seong-Cheol Lee und Suyoung Seo. „UAV-Based Low Altitude Remote Sensing for Concrete Bridge Multi-Category Damage Automatic Detection System“. Drones 7, Nr. 6 (08.06.2023): 386. http://dx.doi.org/10.3390/drones7060386.

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Detecting damage in bridges can be an arduous task, fraught with challenges stemming from the limitations of the inspection environment and the considerable time and resources required for manual acquisition. Moreover, prevalent damage detection methods rely heavily on pixel-level segmentation, rendering it infeasible to classify and locate different damage types accurately. To address these issues, the present study proposes a novel fully automated concrete bridge damage detection system that harnesses the power of unmanned aerial vehicle (UAV) remote sensing technology. The proposed system employs a Swin Transformer-based backbone network, coupled with a multi-scale attention pyramid network featuring a lightweight residual global attention network (LRGA-Net), culminating in unprecedented breakthroughs in terms of speed and accuracy. Comparative analyses reveal that the proposed system outperforms commonly used target detection models, including the YOLOv5-L and YOLOX-L models. The proposed system’s robustness in visual inspection results in the real world reinforces its efficacy, ushering in a new paradigm for bridge inspection and maintenance. The study findings underscore the potential of UAV-based inspection as a means of bolstering the efficiency and accuracy of bridge damage detection, highlighting its pivotal role in ensuring the safety and longevity of vital infrastructure.

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Li, Xuefei, Jian Li, Lida Su und Yue Cao. „Control Methods for Roll Instability of Articulated Steering Vehicles“. Mathematical Problems in Engineering 2016 (2016): 1–14. http://dx.doi.org/10.1155/2016/8041816.

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This study examines the control methods for roll instability of articulated steering vehicles (ASVs) by taking wheel loaders as the research object. An eight-degrees-of-freedom nonlinear dynamics model of ASVs was built on the basis of multibody dynamics. Three methods, namely, active braking (the front and rear axles have the same braking torque), active steering, and adjusting the swing bridge (applying a control torque between the rear body and rear axle), were adopted to analyze the effects on the roll stability of ASVs through the dynamic model. The results show that active braking is conducive to the roll stability of ASVs during turning, active steering can improve the roll stability of ASVs during turning and passing over obstacles, and adjusting the swing bridge can improve the roll stability of ASVs by changing the vehicle posture and the position of the gravity center.

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Maruyama, Tadaaki, Eiichi Watanabe und Hiroshi Tanaka. „Floating Swing Bridge with a 280 m Span, Osaka“. Structural Engineering International 8, Nr. 3 (August 1998): 174–75. http://dx.doi.org/10.2749/101686698780489216.

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Monti, Giorgio, Giuseppe Quaranta und Giuseppe C. Marano. „Sensor Network Design for Monitoring a Historic Swing Bridge“. Key Engineering Materials 517 (Juni 2012): 717–23. http://dx.doi.org/10.4028/www.scientific.net/kem.517.717.

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Significant advances in the development and customization of various sophisticated technologies for structural monitoring have emerged during the last decade. Technologies for instrumentation, monitoring, load testing, non-destructive evaluation and/or characterization, three-dimensional finite element modeling and various types of analyses have now become available at a reasonable cost. Within this framework, the paper focuses the issues addressed in designing a sensors network for dynamic monitoring of a historic swing bridge in Taranto (Italy).

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Cao, Xiaohua, Chao Meng, Yong Zhou und Meng Zhu. „An improved negative zero vibration anti-swing control strategy for grab ship unloader based on elastic wire rope model“. Mechanics & Industry 22 (2021): 45. http://dx.doi.org/10.1051/meca/2021045.

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A dynamic model of swing system of bridge-type ship unloader is established by considering the elastic factor of wire rope in this paper. Based on this model, an improved Negative Zero Vibration (NZV) shaper with optimal control parameters of variable rope length system is proposed to restrain the swing of grab. Then the control effects, influence of elasticity factor and parameter sensitivities are analyzed based on numerical simulation. The results show that the proposed control strategy can reduce the working cycle time of the grab ship unloader about 11% when considering the elastic factor of the wire rope, and the grab's maximum residual swing angle decreases by 67% when discharging at full load, and decreases by 79% when taking the cargos at empty load. This implies that the improved NZV control method provides better swing angle control performance and shorter operation time compared with the Zero Vibration (ZV) and Zero Vibration and Derivative (ZVD) methods. Moreover, elastic rope model can improve the swing angle control effect of grab based on the proposed control strategy compared with rigid rope model. The parameter sensitivity analysis displays that the grab's maximum residual swing angle by using the improved NZV method is sensitive to the change of the grab's center of gravity, and this angle is more sensitive to the wire rope diameter deviation compared with the elastic modulus deviation.

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Wu, Xianqing, und Xiongxiong He. „Control of the bridge crane by constructing a Lyapunov function: theoretical design and experimental verification“. Transactions of the Institute of Measurement and Control 39, Nr. 12 (10.05.2016): 1763–70. http://dx.doi.org/10.1177/0142331216646823.

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For the control problem of bridge cranes, it is challenging to realize fast transportation and efficient swing suppression simultaneously. Motivated by this observation, in this paper, we aim to propose a nonlinear controller achieving these objectives by constructing a desired Lyapunov function. In particular, a constructive Lyapunov function is introduced in a segmented manner. Based on that, a nonlinear control method rendering the dissipation inequality with respect to the constructed Lyapunov function is proposed straightforwardly, which achieves precise trolley positioning along with efficient payload swing elimination. The corresponding stability and convergence analysis is guaranteed by Lyapunov techniques and LaSalle’s invariance principle. Simulation and experimental results are provided to demonstrate the effectiveness and feasibility of the proposed method.

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Zhao, Huihui, Jianxin Chen, Qi Shi, Xueling Ma, Yi Yang, Liangtao Luo, Shuzhen Guo, Yong Wang, Jing Han und Wei Wang. „Metabolomics-Based Study of Clinical and Animal Plasma Samples in Coronary Heart Disease with Blood Stasis Syndrome“. Evidence-Based Complementary and Alternative Medicine 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/638723.

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The aim of this study is to explore a bridge connecting the mechanism basis and macro syndromes of coronary heart disease with experimental animal models. GC-MS technique was used to detect the metabolites of plasma samples in mini swine models with myocardial infarction (MI) and patients with unstable angina (UA). 30 metabolites were detected in the plasma samples of more than 50 percent of model group and control group in swine, while 37 metabolites were found in the plasma samples of UA patients and healthy control group. 21 metabolites in the plasma samples of swine model and 20 metabolites in patients with UA were found of significant value. Among which, 8 shared metabolites were found of low level expression in both swine model and UA patients. Independent Student’st-test, principal component analysis (PCA), and hierarchicalcluster analysis (HCA) were orderly applied to comprehend inner rules of variables in the data. The 8 shared metabolites could take place of the 21 or 20 metabolites in classification of swine model with MI and UA patients, which could be considered as a bridge connecting the mechanism basis and macrosyndromes of swine model with MI and UA patients.

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Yao, Zhi-Yuan, Guo-Qin Zhang, Wan-Wan Yao, Xiao-Zu Wang, Yin Qian und Xiao-Ming Ren. „Uniaxial thermal expansion behaviors and ionic conduction in a layered (NH4)2V3O8“. Dalton Transactions 49, Nr. 30 (2020): 10638–44. http://dx.doi.org/10.1039/d0dt01833c.

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Layered (NH₄)₂V₃O₈ exhibits ZTE and NTE behaviors along the c-axis, and ZTE nature along the a-axis owing to swing-like movement of vanadyl in VO₄ tetrahedra and transverse vibration of bridged O atoms connecting VO₄ tetrahedra.

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Liu, Zhongye, Chuntong Liu, Zhenxin He, Yuanying Gan und Bojian Li. „Analysis of Coupled Vibration and Swing Characteristics of Bridge Crane“. Journal of Physics: Conference Series 2012, Nr. 1 (01.09.2021): 012016. http://dx.doi.org/10.1088/1742-6596/2012/1/012016.

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